[WIP] Add co-scheduling functionality for GPUs using MPS

[kulnaman]

This PR introduces support for GPU co-scheduling directly within the scheduler framework. Previously, users needed to manually provide their own resource (R), bypassing the scheduler's resource allocation logic. With this update:

1. Users can specify that a job is eligible for co-scheduling.
2. The scheduler will automatically handle resource allocation for such jobs.

Currently there is a simple co-scheduling policy(cosched):

1. Prioritizes GPUs with no running jobs for resource allocation.
2. Distributes MPS resources efficiently among jobs sharing a GPU.
   One can run the simple policy by simply:

resource-query -L mps_data/small.graphml -F pretty_simple --match-subsystems=CA --match-policy=cosched
resource-query> match allocate mps_data/job_1.yaml

Pending Work:

1. Assign appropriate MPS % to each job.
2. Communicate this to flux-core.

[codecov]

Codecov Report

Attention: Patch coverage is 39.23077% with 79 lines in your changes missing coverage. Please review.

Project coverage is 71.4%. Comparing base (6a7ecc0) to head (f90cf68).

Files with missing lines	Patch %	Lines
resource/policies/dfu_match_cosched_aware.cpp	0.0%	60 Missing ⚠️
resource/libjobspec/jobspec.cpp	59.3%	13 Missing ⚠️
resource/policies/dfu_match_policy_factory.cpp	33.3%	2 Missing ⚠️
resource/traversers/dfu_impl_update.cpp	33.3%	2 Missing ⚠️
resource/traversers/dfu.cpp	85.7%	1 Missing ⚠️
resource/traversers/dfu_impl.cpp	90.0%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #1317     +/-   ##
========================================
- Coverage    75.2%   71.4%   -3.8%     
========================================
  Files         111     112      +1     
  Lines       15986   16105    +119     
========================================
- Hits        12029   11510    -519     
- Misses       3957    4595    +638     

Files with missing lines	Coverage Δ
resource/evaluators/scoring_api.cpp	88.0% <100.0%> (+2.6%)	⬆️
resource/evaluators/scoring_api.hpp	81.2% <ø> (ø)
resource/libjobspec/jobspec.hpp	100.0% <ø> (ø)
resource/modules/resource_match.cpp	59.8% <ø> (-9.7%)	⬇️
resource/policies/base/dfu_match_cb.cpp	35.4% <100.0%> (+2.8%)	⬆️
resource/policies/dfu_match_locality.cpp	8.0% <ø> (ø)
resource/policies/dfu_match_multilevel_id.hpp	0.0% <ø> (ø)
resource/policies/dfu_match_multilevel_id_impl.hpp	81.9% <ø> (ø)
resource/policies/dfu_match_var_aware.cpp	87.2% <ø> (ø)
resource/utilities/command.cpp	74.4% <100.0%> (-3.2%)	⬇️
... and 7 more

... and 17 files with indirect coverage changes